Robert W. "Bob" Jensen, P.E.
bjensen@jensenengineers.com

Michael S. Jensen, P.E.
mjensen@jensenengineers.com

972-994-9872
972-994-0747
972-692-5713 fax

CASE STUDIES - Drainage Control

Also see Retaining Wall Failure and Slab Upheaval

The importance of maintaining a consistent moisture content in supporting soils cannot be overemphasized.  It is important to keep soils from experiencing excessive moisture gain during storm events by providing a positive flow of runoff away from the perimeter. 

In this regard, initial efforts should include installation of guttering at drip lines.  Beyond this, a positive grade should exist at all perimeters.

We regularly encounter more complex situation than simple re-grading.  This photo shows a remediation for water penetrating into this home due to a negative slope from adjoining building site.  A swale was constructed to remove larger quantities of water, coupled with a shallow French drain at base of retaining wall, acting as a continuous surface drain. 

 

Here a driveway was installed at higher elevation than the slab floor, allowing water to flow towards and pond near the building.  During more severe rainfalls, this water penetrated into the building, wetting carpets and baseboards while damaging wooden structural framing.  Discharge is through curb shown below.


Subsurface water emerging through joints in concrete roadway.